Quantum well transistor devices formed in epitaxially grown semiconductor heterostructures, typically in III-V or silicon-germanium/germanium (SiGe/Ge) material systems, offer exceptionally high carrier mobility in the transistor channel. In addition, these devices provide exceptionally high drive current performance. However, non-planar quantum well transistors tend to exhibit charge spill-over and an electrically poor high-k dielectric and germanium interface at least by virtue of the thin high-k material, in this deleteriously affecting the performance of the device.